IEC 62319-1:2005

INTERNATIONAL IEC
STANDARD 62319-1
First edition
2005-02
Polymeric thermistors –
Directly heated positive step function
temperature coefficient –
Part 1:
Generic specification
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INTERNATIONAL IEC
STANDARD 62319-1
First edition
2005-02
Polymeric thermistors –
Directly heated positive step function
temperature coefficient –
Part 1:
Generic specification
 IEC 2005  Copyright - all rights reserved
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International Electrotechnical Commission
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For price, see current catalogue

– 2 – 62319-1  IEC:2005(E)
CONTENTS
FOREWORD.4

1 General .6
1.1 Scope.6
1.2 Normative references .6
2 Technical data.7
2.1 Units and symbols .7
2.2 Terms and definitions.7
2.3 Preferred values .10
2.4 Marking .11
3 Quality assessment procedures .11
3.1 General .11
3.2 Primary stage of manufacture .11
3.3 Subcontracting .12
3.4 Structurally similar components .12
3.5 Qualification approval procedures .12
3.6 Rework and repair .18
3.7 Release for delivery.18
3.8 Certified test records of released lots .19
3.9 Delayed delivery.19
3.10 Alternative test methods .19
3.11 Manufacture outside the geographical limits of IECQ NSIs.19
3.12 Unchecked parameters .19
4 Test and measurement procedures .19
4.1 Standard conditions for testing.19
4.2 Drying and recovery.20
4.3 Visual inspection and check of dimensions.20
4.4 Zero power resistance .21
4.5 Insulation resistance (for insulated types only) .21
4.6 Voltage proof (for insulated types only) .22
4.7 Robustness of terminations (for leaded types only).22
4.8 Soldering.23
4.9 Mounting .23
4.10 Rapid change of temperature .24
4.11 Climatic sequence .24
4.12 Cycle life testing .25
4.13 Trip endurance .27
4.14 Trip current .28
4.15 Hold current .28
4.16 Residual current and power dissipation .29
4.17 Time-to-trip .29
4.18 Cold environmental electrical cycling.30
4.19 Thermal runaway.30

62319-1  IEC:2005(E) – 3 –
Annex A (normative) Fixed sample size test schedules for qualification approval.31
Annex B (normative) Vibration-, bump-, shock-, shear-, substrate bending test.32
B.1 Vibration .32
B.2 Bump .32
B.3 Shock.33
B.4 Shear (adhesion) test .33
B.5 Substrate bending test.33

Figure 1 – Test schedule flow chart.15
Figure 2 – Circuit for Trip endurance .28

Table 1 – Fixed sample size test schedule for qualification approval of Polymeric PTC
thermistors for current limitation, assessment level EZ.16
Table 2 – Quality conformance inspection for lot-by-lot inspection.17
Table 3 – Quality conformance inspection for periodic testing .18
Table 4 – Loading weight for wire terminations .22
Table 5 – Number of cycles.25

– 4 – 62319-1  IEC:2005(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
POLYMERIC THERMISTORS –
DIRECTLY HEATED POSITIVE STEP FUNCTION
TEMPERATURE COEFFICIENT –
Part 1: Generic specification
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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International Standard IEC 62319-1 has been prepared by IEC technical committee 40:
Capacitors and resistors for electronic equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
40/1505/FDIS 40/1534/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

62319-1 © IEC:2005(E) – 5 –
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
The contents of the corrigendum of March 2009 have been included in this copy.

– 6 – 62319-1  IEC:2005(E)
POLYMERIC THERMISTORS –
DIRECTLY HEATED POSITIVE STEP FUNCTION
TEMPERATURE COEFFICIENT –
Part 1: Generic specification
1 General
1.1 Scope
This part of IEC 62319 prescribes terms and methods of test for polymeric positive
temperature coefficient thermistors, insulated and non-insulated types, typically intended for
use in current limiting and overcurrent protection
...